As conventional technology related to collection of information enabling identification of a vehicle position by a server, technology has been proposed in which an automobile detects a parked vehicle in front, calculates longitude and latitude of the parked vehicle, and transmits the longitude and latitude to a driving assistance server. In such technology, the driving assistance server collects received longitudes and latitudes, uses these to compute a passable area that takes the parked vehicle into consideration, and transmits information regarding the passable area to the automobile mentioned above. The automobile accordingly updates a guided travel route.